The Mexican legal framework governing customs and foreign trade has evolved toward a stricter and more controlled compliance model. Authorities no longer require importers merely to identify the goods being imported; they now also require proof of the terms and conditions under which the foreign trade transaction is conducted: when it must be performed, how and where it is executed, with whom, the relationship between the parties, and the underlying commercial intent, among other elements which, taken together, demonstrate the materiality of the transaction, in other words, that it exists, is real, verifiable, and was effectively carried out.

Importers must maintain an electronic file for each transaction that includes the customs entry (pedimento) and supporting documentation such as invoices, proof of payment, valuation information, transportation documents, origin documentation, bonds, compliance with non-tariff regulations and restrictions, and technical and commercial identification of the goods (weight, volume, serial numbers, parts, brand, model, etc.), among others.

However, this is no longer sufficient. Recent amendments to customs legislation have expanded these requirements to include additional documentation demonstrating that the foreign trade transaction was effectively carried out and that the goods were actually destined to the customs regime declared in the customs entry or corresponding customs document. Such documentation must also allow verification that the declared value was determined in accordance with applicable legal provisions.

Contracts Evidencing the Foreign Trade Transaction

Among the additional documentation intended to demonstrate the materiality of the foreign trade transaction, and forming part of the importer’s electronic file, contracts executed between the importer and its suppliers or customers play a central role. Generally, these relate to:

• The purchase of the goods or related services.
• The lease or ownership of facilities where imported goods are stored or where production takes place.
• The lease or ownership of machinery and equipment used in the operation.
• Specialized services such as transportation, handling, storage, or production.
• Rights of use and commercialization of intellectual property, where applicable.

It is important to note that, in addition to contracts, applicable legal provisions also contemplate other documents which, in the absence of or as a supplement to contracts, may be required depending on the nature of the transaction. These may include amendments and annexes, purchase orders, title documents, proof of payment, and related documentation.       

Accordingly, a regulatory expectation is established whereby the authority presumes the existence of sufficient documentation enabling it to verify the economic and legal terms agreed upon between the importer and third parties, as well as the substance and traceability of the transaction.

Contracts Attached to the Customs Value Manifest

With respect to the documentation and evidence required to substantiate the declared value of the goods, customs legislation provides that the importer must submit, as part of the customs value declaration, certain elements including contracts and, where applicable, purchase orders related to the transaction.

In this context, a purchase order may be sufficient, provided it contains the essential elements of a contract and that its terms and conditions are clear, complete, and consistent with the electronic file of the transaction. While the provision includes the phrase “where applicable” regarding purchase orders (suggesting that they are required only when they exist), the term “contracts” appears directly and without condition.

Thus, although a technical debate may persist regarding the formal obligation to execute a contract and/or purchase order in every case, from a conservative and enhanced compliance perspective, the absence of a contract and, where applicable, a purchase order, could be interpreted as a weakness in substantiating both the declared value and the materiality of the transaction.

Consequently, maintaining such documentation is not merely a good commercial practice; in the current environment of customs enforcement, it is effectively an indispensable component of compliance control and verification within customs and foreign trade operations.

General Considerations Regarding Contracts

In general, contracts (or documentation capable of verifying the economic and legal terms agreed upon between the importer and third parties) must be consistent and aligned with the information contained in the importer’s electronic file. The data and information as a whole must be coherent and reflect the symmetry of the transaction, thereby supporting the proper determination of customs value.

As a starting point, and depending on the specific nature of each transaction, the following should be clearly established and identified:

• The parties involved.
• The legal capacity of each party (seller, buyer, lessor, lessee, service provider, etc.), as applicable with respect to raw materials, machinery, equipment, or finished products.
• The object and scope of the contract.
• The date of execution, effective date, and term.
• The price or consideration, including place, time, and method of payment, and, where applicable, the applicable exchange rate.
• Allocation of risks and insurance coverage.
• Transportation terms, freight, and place of delivery.
• Loading, unloading, and handling activities.
• Allocation of customs, tariff, and regulatory compliance responsibilities.
• The agreed INCOTERM, where applicable.
• Any other charges or elements affecting the determination of customs value.

Additionally, for greater legal certainty, contracts may include clauses relating to labor and subcontracting restrictions, governing law, jurisdiction and venue, force majeure, language, notices, termination, cancellation, rescission, assignment, amendments, and provisions concerning the relationship or independence of the parties, among others.

Importers should also request documentation from their counterparties evidencing legal existence and authority to act, such as articles of incorporation, powers of attorney, permits, authorizations, identification documents, and tax registrations. It is likewise advisable to verify the corporate purpose, tax identification numbers, names, signatures, and other elements confirming the legitimacy and legal capacity of the parties.

Early planning for contract formalization is essential. Importers should be prepared for a potentially formalistic and lengthy process involving multiple rounds of review and negotiation, which may extend over weeks, months, or even years.

The starting point for any document intended to verify the economic and legal terms agreed upon between the importer and a third party, whether a contract or a purchase order, is to ensure that the essential elements of a contract are present: (a) consent, and (b) a lawful and possible object.

Although Mexican law recognizes that consent may be expressed expressly (verbally, in writing, by electronic or optical means, through any other technology, or by unequivocal signs), or tacitly (through acts or conduct that presume or authorize its presumption), for purposes of enabling the importer to substantiate the materiality of the transaction and comply with the requirement to incorporate it into the electronic file, it is highly advisable that the document be documented in writing and duly signed by the parties

Conclusion

In Mexico, following recent customs reforms, contracts have become a strategic component of customs and foreign trade operations, now constituting an indispensable element of the importer’s electronic file and a relevant factor in substantiating declared value and transaction materiality.

A well-structured contract that is technically sound and consistent with the supporting documentation, not only provides legal certainty to the parties but also strengthens the importer’s position in the face of potential audit or verification procedures by demonstrating the economic and legal substance of the transaction. More than a formal requirement, the contract has consolidated itself as a strategic evidentiary tool within the current regulatory framework.

Early contractual planning, proper identification of essential elements, and formal written execution are now key preventive measures in an increasingly technical and document-driven enforcement environment.

This is the right moment for importers to ensure they maintain contracts that provide legal certainty and mitigate legal risks. In this context, contractual formalization ceases to be merely a corporate or commercial practice and becomes an essential component of customs and foreign trade compliance.

Legal Disclaimer: This article is for informational purposes only and does not constitute legal advice by Braumiller Law PLLC, its members, or the author. The application of customs and foreign trade provisions depends on the specific circumstances of each transaction. Specialized legal advice should be obtained before making any decision based on the content of this document. Please send your valuable comments and contributions to bob@braumillerlaw.com and brenda@braumillerlaw.com.